WO2020021640A1

WO2020021640A1 - User device and base station device

Info

Publication number: WO2020021640A1
Application number: PCT/JP2018/027754
Authority: WO
Inventors: 良介大澤; 佑一柿島; 聡永田
Original assignee: 株式会社Ｎｔｔドコモ
Priority date: 2018-07-24
Filing date: 2018-07-24
Publication date: 2020-01-30
Also published as: US20210266995A1; JP2023158020A; US11903055B2; EP3829123A1; JPWO2020021640A1; CN112425126B; EP3829123A4; CN112425126A

Abstract

This user device has a receiving unit which, from a base station device or a first user device, receives information relating to the arrangement of a reference signal used in direct communication between terminals, a control unit which determines a signal of the direct communication between terminals on the basis of the information relating to the arrangement of the reference signal used in said direct communication between terminals, and a transmission unit which transmits the determined signal of the direct communication between terminals to a second user device, wherein the information relating to the arrangement of the reference signal used in the direct communication between terminals includes the transmission density of the reference signal used in the direct communication between terminals.

Description

User equipment and base station equipment

<< The present invention relates to a user apparatus and a base station apparatus in a wireless communication system.

In LTE (Long Term Evolution) and a successor system to LTE (for example, LTE-A (LTE Advanced), NR (New Radio) (also referred to as 5G)), direct communication between user devices is not performed via a wireless base station. A D2D (Device @ to \ Device) technique to be performed has been studied (for example, Non-Patent Document 1).

D2D reduces traffic between a user apparatus and a base station apparatus, and enables communication between user apparatuses even when the base station apparatus becomes unable to communicate during a disaster or the like. In 3GPP (3rd Generation Partnership Project), D2D is referred to as “sidelink”, but in this specification, D2D which is a more general term is used. However, in the following description of the embodiments, side links are used as necessary.

D2D communication includes D2D discovery (D2D @ discovery, also referred to as D2D discovery) for discovering another communicable user device, and D2D communication (D2D @ direct @ communication, D2D communication, terminal for direct communication between user devices). Inter-direct communication, etc.). In the following, D2D communication, D2D discovery, and the like are simply referred to as D2D unless otherwise distinguished. A signal transmitted and received in D2D is called a D2D signal. Various use cases of a service related to V2X (Vehicle to Everything) in NR are being studied (for example, Non-Patent Document 2).

In V2X, vehicles and the like on which the user devices are mounted move in different directions when passing each other, and therefore, it is assumed that the communication environment changes rapidly with a change in relative speed. However, a reference signal that can adapt to a rapidly changing communication environment has not been used.

The present invention has been made in view of the above points, and has as its object to use an appropriate reference signal in direct communication between terminals.

According to the disclosed technology, a receiving unit that receives information related to an arrangement of reference signals used for direct communication between terminals from a base station apparatus or a first user apparatus, and an arrangement of reference signals used for direct communication between terminals A control unit that determines a signal for direct terminal-to-terminal communication based on the information according to (1), and a transmitting unit that transmits the determined signal for direct terminal-to-terminal communication to a second user device; The user apparatus is provided with the information on the arrangement of the reference signal used for communication, including the transmission density of the reference signal used for direct communication between terminals.

According to the disclosed technology, an appropriate reference signal can be used in direct communication between terminals.

It is a figure for explaining V2X. FIG. 4 is a diagram illustrating an example of an arrangement of reference signals according to the embodiment of the present invention. It is a figure showing example (1) of a communication situation in an embodiment of the invention. It is a figure showing example (2) of a communication situation in an embodiment of the invention. FIG. 3 is a sequence diagram for explaining SL communication according to the embodiment of the present invention. 6 is a flowchart for explaining SL communication transmitted to a plurality of user devices 20 according to the embodiment of the present invention. FIG. 2 is a diagram illustrating an example of a functional configuration of a base station device 10 according to an embodiment of the present invention. FIG. 2 is a diagram illustrating an example of a functional configuration of a user device 20 according to the embodiment of the present invention. FIG. 3 is a diagram illustrating an example of a hardware configuration of the base station device 10 or the user device 20 according to the embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. The embodiment described below is an example, and the embodiment to which the present invention is applied is not limited to the following embodiment.

既存 In the operation of the wireless communication system according to the embodiment of the present invention, existing technology is used as appropriate. However, the existing technology is, for example, existing LTE, but is not limited to existing LTE. Further, the term “LTE” used in this specification has a broad meaning including LTE-Advanced and a scheme after LTE-Advanced (eg, NR), unless otherwise specified.

Further, in the embodiment of the present invention, the duplex system may be a TDD (Time Division Duplex) system, an FDD (Frequency Division Duplex) system, or any other system (for example, Flexible Duplex). May be used.

In the following description, a method of transmitting a signal using a transmission beam may be digital beamforming for transmitting a signal multiplied by a precoding vector (precoded with a precoding vector), Analog beamforming that achieves beamforming using a variable phase shifter in an RF (Radio @ Frequency) circuit may be used. Similarly, the method of receiving a signal using a reception beam may be digital beamforming that multiplies a received signal by a predetermined weight vector, or realizes beamforming using a variable phase shifter in an RF circuit. Analog beam forming. Hybrid beamforming combining digital beamforming and analog beamforming may be applied. Also, transmitting a signal using a transmission beam may be transmitting a signal at a specific antenna port. Similarly, receiving a signal using a receive beam may be receiving a signal at a particular antenna port. An antenna port refers to a logical antenna port or a physical antenna port defined in the 3GPP standard. Also, the precoding or beamforming may be referred to as a precoder or a spatial domain filter (Spatial \ domain \ filter).

In addition, the method of forming the transmission beam and the reception beam is not limited to the above method. For example, in the base station apparatus 10 or the user apparatus 20 including a plurality of antennas, a method of changing the angle of each antenna may be used, or a method of combining a method using a precoding vector and a method of changing the angle of the antenna may be used. Alternatively, a different antenna panel may be used by switching, a method combining a plurality of antenna panels may be used, or another method may be used. Further, for example, a plurality of different transmission beams may be used in a high frequency band. The use of a plurality of transmission beams is called multi-beam operation, and the use of one transmission beam is called single-beam operation.

Further, in the embodiment of the present invention, the “configure” of the wireless parameter or the like may mean that a predetermined value is set in advance (Pre-configure), or the base station apparatus 10 Alternatively, a wireless parameter notified from the user device 20 may be set.

FIG. 1 is a diagram for explaining V2X. In 3GPP, realization of V2X (Vehicle to Everything) or eV2X (enhanced V2X) by expanding the D2D function has been studied, and specifications are being promoted. As shown in FIG. 1, V2X is a part of ITS (Intelligent Transport Systems) and means V2V (Vehicle to to Vehicle), which means a form of communication performed between cars, and a roadside installed on the side of a car and a road. V2I (Vehicle-to-Infrastructure), which means a form of communication performed with an RSU (Road-Side @ Unit), and V2N (Vehicle-to-infrastructure), which means a form of communication performed between an automobile and a mobile terminal possessed by a driver. Nomadic device, and V2P (Vehicle to Pedestrian) meaning a form of communication between a car and a mobile terminal carried by a pedestrian.

Also, 3GPP is studying V2X using LTE or NR cellular communication and terminal-to-terminal communication. It is assumed that studies on L2 or NR V2X not limited to the 3GPP specifications will be made in the future. For example, ensuring interoperability, reducing costs by implementing higher layers, using or switching multiple RATs (Radio Access Technology), supporting regulations in each country, acquiring data from LTE or NR V2X platforms, distributing, managing databases, It is assumed that usage methods will be considered.

において In the embodiment of the present invention, a form in which the communication device is mounted on a vehicle is mainly assumed, but the embodiment of the present invention is not limited to this form. For example, the communication device may be a terminal held by a person, the communication device may be a device mounted on a drone or an aircraft, or the communication device may be a base station, an RSU, a relay station (relay node), or the like. It may be.

Note that SL (Sidelink) may be distinguished from UL (Uplink) or DL (Downlink) based on any one or combination of the following 1) -4). SL may be another name.
1) Resource allocation in the time domain 2) Resource allocation in the frequency domain 3) Synchronization signal to be referred to (including Sidelink Synchronization Signal (SLSS))
4) Reference signal used for path loss measurement for transmission power control

Also, regarding SL or UL OFDM (Orthogonal Frequency Division Multiplexing), CP-OFDM (Cyclic-Prefix OFDM), DFT-S-OFDM (Discrete Fourier Transform-Spread-OFDM), Transform not pre-coded or non-transformed non-transformed OFDM Any of the available OFDMs may be applied.

In the LTE SL, Mode 3 and Mode 4 are defined for SL resource allocation to the user apparatus 20. In Mode 3, transmission resources are dynamically allocated by DCI (Downlink \ Control \ Information) transmitted from the base station apparatus 10 to the user apparatus 20. In Mode 3, SPS (Semi \ Persistent \ Scheduling) is also possible. In Mode 4, the user device 20 autonomously selects a transmission resource from the resource pool.

FIG. 2 is a diagram showing an example of the arrangement of reference signals according to the embodiment of the present invention. FIG. 2 shows an example in which a reference signal is arranged in a resource on a radio frame specified by an OFDM symbol (OFDM symbol) corresponding to the time domain and a subcarrier (Subcarrier) corresponding to the frequency domain. As the OFDM symbol, 14 from # 0 to # 13 is shown, which corresponds to one slot in NR. 12 subcarriers from # 0 to # 11 are shown and correspond to one resource block. Although FIG. 2 shows an example of a DL radio frame of NR, a similar arrangement of reference signals may be performed in a UL or SL radio frame.

ＰＤAs shown in FIG. 2, PDCCH (Physical downlink control channel) is arranged in one resource block in OFDM symbols # 0 and # 1. DMRS (Demodulation reference signal) is arranged in one resource block in OFDM symbols # 2 and # 11. DMRS is a reference signal mainly used for demodulation. The DMRS arranged in OFDM symbol # 2 may be referred to as Front-loaded @ DMRS, and the DMRS arranged in OFDM symbol # 11 may be referred to as Additional @ DMRS. PTRS (Phase tracking reference signal) is allocated to subcarrier # 0 of OFDM symbols # 4, # 6, # 8, # 10, and # 13. PTRS is a reference signal mainly used for phase correction. CSI-RS (Channel-state information reference signal) (8-port) is allocated to subcarriers # 4, # 5, # 8 and # 9 of OFDM symbols # 5 and # 6. CSI-RS (8-port) is mainly used for channel state estimation. 8-port indicates an antenna port through which the CSI-RS is transmitted. CSI-RS for tracking is allocated to subcarriers # 3, # 7, and # 11 of OFDM symbols # 4 and # 8. CSI-RS @ for @ tracking is mainly used for time domain and frequency domain tracking.

In scenarios of millimeter wave transmission and high-speed movement in NR, tracking accuracy is required to reduce noise in the frequency and / or time domain. Therefore, the above-mentioned PTRS and CSI-RS for tracking are supported. The transmission intervals of the PTRS and the CSI-RS are set semi-statically.

FIG. 3 is a diagram illustrating an example (1) of a communication situation according to the embodiment of the present invention. When PTRS and / or CSI-RS are supported in the SL communication, as shown in FIG. 3, when the vehicles on which the user device 20A and the user device 20B are respectively mounted pass each other, the relative speed of the transmitting / receiving terminal suddenly increases. Therefore, it is necessary to more dynamically control the transmission density of the PTRS and / or the CSI-RS. By controlling the transmission density of the PTRS and / or the CSI-RS more dynamically, the quality of the SL communication can be improved using a reference signal adapted to a changing communication environment. The PTRS introduced into the SL may be called “SL-PTRS”, and the CSI-RS introduced into the SL may be called “SL-CSI-RS”.

FIG. 4 is a diagram illustrating an example (2) of a communication situation according to the embodiment of the present invention. As shown in FIG. 4, when the user device 20A performs multicast or broadcast to the

user devices

20B, 20C, and 20D in the SL communication, the PTRS and / or CSI-RS settings are performed for any of the user devices 20 in the SL communication. Is not uniquely determined. Therefore, it is necessary to define the setting of PTRS and / or CSI-RS when performing multicast or broadcast in SL communication.

FIG. 5 is a sequence diagram for explaining SL communication according to the embodiment of the present invention. A procedure in which the base station apparatus 10 or the user apparatus 20 having the scheduling capability dynamically designates the SL-PTRS and / or SL-CSI-RS to the user apparatus 20 that performs the SL transmission will be described with reference to FIG. The user device 20 having the scheduling capability is based on an instruction from the base station device 10 or autonomously, with respect to another user device 20, for MCS (Modulation and Coding Scheme), TBS (Transport block size), rank or transmission layer. The user device 20 determines and notifies at least one of the number, resource allocation, transmission power, and transmission timing.

In step S11, the base station device 10 specifies the transmission density of the SL-PTRS and / or SL-CSI-RS to the user device 20A via PHY (Physical) layer signaling or MAC (Medium Access Control) layer signaling. The transmission pattern of the SL-PTRS and / or SL-CSI-RS that is a switching candidate is defined in advance in the specification or acquired by the user device 20A by RRC (Radio Resource Control) setting. The base station apparatus 10 notifies the user apparatus 20A of the index corresponding to the transmission pattern via PHY layer signaling or MAC layer signaling, so that the user apparatus 20A transmits the SL-PTRS and / or SL-CSI-RS. The pattern may be switched.

For example, the transmission pattern of SL-PTRS and / or SL-CSI-RS includes one or more of the following 1) to 5).
1) Mapping pattern in frequency domain and time domain in resource or resource pool 2) Start position and end position of RE (Resource element) where reference signal is placed 3) RE interval where reference signal is placed 4) Reference signal 5) RB (Resource block) interval in which reference signal is allocated 5) Index of slot in which reference signal is allocated

The designation of the transmission pattern of the SL-PTRS and / or SL-CSI-RS in step S11 is performed by PHY layer signaling or MAC layer signaling via a DL signal such as a PBCH (Physical broadcast channel), a PDCCH or a PDSCH (Physical downlink link shared channel). May be performed.

The base station device 10 in steps S11 and S14 may be replaced with a user device 20 having scheduling capability. When replaced, the designation of the transmission pattern of the SL-PTRS and / or SL-CSI-RS in step S11 may be PSBCH (Physical Sidelink Broadcast channel), PSCCH (Physical Sidelink Control Channel), PSSCH (Physical Sidelink Shared Channel), or the like. May be performed by PHY layer signaling or MAC layer signaling via an SL signal. Also, the designation of the transmission pattern of the SL-PTRS and / or SL-CSI-RS in steps S11 and S14 may be determined based on the sequence of the reference signal. The reference signal is, for example, a sequence of SL-PTRS, SL-CSI-RS or SLSS, and even if the sequence of the reference signal received in the resource element where the reference signal is arranged in common for all transmission patterns is determined. Good. In steps S12, S15, S16, and S18, the user device 20B may determine the transmission pattern of SL-PTRS and / or SL-CSI-RS based on the sequence of the corresponding reference signal.

In step S12, the user device 20A transmits the SL signal determined based on the setting of the reference signal instructed from the base station device 10 to the user device 20B. By switching the transmission pattern of SL-PTRS and / or SL-CSI-RS based on the reference signal setting instruction, the user device 20A can change the transmission density of the reference signal necessary for SL communication.

In step S13, the user device 20B transmits the feedback of the SL reception status to the base station device 10. The information to be fed back includes one or more of the following 1) -4).
1) CQI (Channel quality indicator), BLER (Block error rate), RSRP (Reference signal received power), RSRQ (Reference signal received quality), SINR (Signal-to-Interference plus Noise power Ratio), Doppler shift amount, etc. Information indicating the reception quality or moving speed of the mobile terminal. It may be referred to, for example, as SL-CQI, SL-BLER, etc., to indicate that it is based on SL measurement or decoding.
2) One or more bits of information that directly indicate an increase or decrease in the density of SL-PTRS and / or SL-CSI-RS. The information of two bits or more may indicate a rise or fall that is greater than the rise or fall indicated by the one-bit information.
3) Information indicating a transmission pattern of SL-PTRS and / or SL-CSI-RS.
4) 1-bit flag. For example, it is transmitted when requesting an increase in the density of SL-PTRS and / or SL-CSI-RS.

Note that the feedback in step S13 may be transmitted to the base station apparatus 10 as a UL signal via the PUCCH (Physical uplink control channel) or PUSCH (Physical uplink shared channel), or may be transmitted as an SL signal via the PSCCH or PSSCH. It may be transmitted to the transmitting user apparatus 20 or the user apparatus 20 having the scheduling capability.

In step S14, based on the feedback of the SL reception status received from the user device 20B, the base station device 10 sets the setting of the reference signal determined to adapt to the SL reception status in the user device 20B in the same manner as in step S11. Transmit to the user device 20B. In step S15, the user device 20A transmits the SL signal determined based on the setting of the reference signal instructed from the base station device 10 to the user device 20B as in step S12. For example, after step S15, the user device 20B may transmit the feedback of the SL reception status to the base station device 10 as in step S13.

Note that the transmitting user apparatus 20 may autonomously switch the transmission pattern of the SL-PTRS and / or SL-CSI-RS. In step S16, the user device 20A performs SL transmission to the user device 20B with the setting of the reference signal determined autonomously. The transmission pattern of the SL-PTRS and / or SL-CSI-RS which is determined autonomously is the same as in step S11.

The transmission pattern of the SL-PTRS and / or SL-CSI-RS may be explicitly notified from the transmitting user apparatus 20A to the receiving user apparatus 20B, or may be blindly detected by the receiving user apparatus 20B. Good. For example, the transmission pattern of SL-PTRS and / or SL-CSI-RS may be explicitly notified by an SL signal via PSBCH, PSCCH or PSSCH, or a sequence of SL-PTRS, CSI-RS or SLSS. May be detected implicitly.

In step S17, the user device 20B transmits the feedback of the SL reception status to the user device 20A in the same manner as in step S13. In step S18, similarly to step S14, the user device 20A sets, based on the feedback of the SL reception status received from the user device 20B, the setting of the reference signal determined to adapt to the SL reception status in the user device 20B, The data is transmitted to the user device 20B as in step S16.

FIG. 6 is a flowchart for explaining SL communication according to the embodiment of the present invention. The setting of the SL reference signal when the user device 20 performs the multicast or broadcast SL communication will be described with reference to FIG. In FIG. 6, the base station device 10 may be replaced with a user device 20 having scheduling capability.

In step S21, the user device 20 performs SL multicast or broadcast. Subsequently, the base station device 10 or the user device 20 that has transmitted the SL receives the feedback related to the SL reception from the plurality of user devices 20 that have received the SL multicast or the broadcast (S22).

In step S23, the base station device 10 or the user device 20 that has transmitted the SL determines the pattern of the reference signal based on the plurality of feedbacks received in step S22. For example, the selection of the transmission pattern of SL-PTRS and / or SL-CSI-RS may be any of the following methods 1) -3).
1) Select a transmission pattern with a high transmission density suitable for the worst case of the reception situation among the feedbacks 2) Select a transmission pattern with a low transmission density suitable for the best case of the reception situation among the feedbacks 3) Median value of the feedback Or select a transmission pattern that has a transmission density that matches the average reception situation

In addition, the feedback to be referred to among the plurality of feedbacks may be the feedback with the best communication quality indicated by RSRP, RSRQ, SINR, or the like, may be the top N feedbacks, or may be the feedback equal to or more than a predetermined threshold. Good. Further, the feedback to be referred to among the plurality of feedbacks may be the feedback having the worst communication quality indicated by RSRP, RSRQ, SINR, or the like, the lower N feedbacks, or the feedback equal to or less than a predetermined threshold. It may be.

The determination of the reference signal pattern in step S23 may be performed by the base station device 10 or the user device 20 having the scheduling capability, or may be performed autonomously by the user device 20 that has transmitted the SL.

In step S24, the user device 20 performs SL multicast or broadcast including a reference signal changed based on the reference signal pattern determined by the base station device 10, the user device 20 having the scheduling capability, or the own device.

The setting of the reference signal described with reference to FIG. 5 or FIG. 6 has been described as an example applied to SL, but may be similarly applied to DL or UL. Further, the reference signal described with reference to FIG. 5 or FIG. 6 is not limited to SL-PTRS and / or SL-CSI-RS, and may be applied to other reference signals and synchronization signals. May be applied to the transmission density or the number of times of repeated transmission in the repeated transmission of control signals and data.

Note that some or all of the SL-PTRS and SL-CSI-RS transmission patterns and / or SL resources may be common to the UL or DL. For example, when the resource is common to the SL and the UL or the DL, the reference signal is shared by the SL and the UL or the DL. In setting the reference signal described in FIG. 5 or FIG. 6, the base station apparatus 10 may be replaced with a relay station or the like in addition to the user apparatus 20 having the scheduling capability.

According to the above-described embodiment, even in an unstable communication environment in which the relative speed between the user devices changes rapidly, direct communication between terminals can be continued by dynamically switching the arrangement pattern of the reference signal. In addition, by switching to a reference signal arrangement pattern determined by the base station apparatus or the user apparatus based on feedback obtained from the receiving-side user apparatus, it is possible to perform direct terminal-to-terminal communication adapted to the communication environment. Further, when the SL communication is multicast or broadcast, it is possible to switch to an appropriate reference signal arrangement pattern.

That is, in the direct communication between terminals, an appropriate reference signal can be used.

(Device configuration)
Next, an example of a functional configuration of the base station device 10 and the user device 20 that execute the processes and operations described above will be described. The base station device 10 and the user device 20 include a function for implementing the above-described embodiment. However, each of the base station device 10 and the user device 20 may include only some of the functions in the embodiment.

<Base station device 10>
FIG. 7 is a diagram illustrating an example of a functional configuration of the base station device 10. As shown in FIG. 7, base station apparatus 10 includes transmitting section 110, receiving section 120, setting section 130, and control section 140. The functional configuration shown in FIG. 7 is only an example. As long as the operation according to the embodiment of the present invention can be executed, the names of the functional divisions and the functional units may be any.

The transmission unit 110 has a function of generating a signal to be transmitted to the user device 20 and transmitting the signal wirelessly. The receiving unit 120 includes a function of receiving various signals transmitted from the user device 20 and acquiring, for example, information of a higher layer from the received signals. In addition, the transmitting unit 110 has a function of transmitting an NR-PSS, an NR-SSS, an NR-PBCH, a DL / UL control signal, and the like to the user device 20. Further, for example, the transmitting unit 110 transmits information indicating that another terminal is approaching the user device 20, and the receiving unit 120 receives terminal information from the user device 20.

The setting unit 130 stores in the storage device the setting information set in advance and various setting information to be transmitted to the user device 20, and reads out the setting information from the storage device as needed. The content of the setting information is, for example, information related to a reference signal of the D2D communication.

The control unit 140 performs the process related to the setting for the user device 20 to perform the D2D communication, as described in the embodiment. In addition, the control unit 140 performs a process related to the reference signal of the D2D communication. A function unit related to signal transmission in control unit 140 may be included in transmitting unit 110, and a function unit related to signal reception in control unit 140 may be included in receiving unit 120.

<User device 20>
FIG. 8 is a diagram illustrating an example of a functional configuration of the user device 20. As illustrated in FIG. 8, the user device 20 includes a transmitting unit 210, a receiving unit 220, a setting unit 230, and a control unit 240. The functional configuration shown in FIG. 8 is merely an example. As long as the operation according to the embodiment of the present invention can be executed, the names of the functional divisions and the functional units may be any.

(4) The transmission unit 210 creates a transmission signal from transmission data, and transmits the transmission signal wirelessly. The receiving unit 220 wirelessly receives various signals and obtains a higher-layer signal from the received physical-layer signal. Further, the receiving section 220 has a function of receiving NR-PSS, NR-SSS, NR-PBCH, DL / UL / SL control signals, and the like transmitted from the base station apparatus 10. In addition, for example, the transmission unit 210 transmits the PSCCH (Physical Sidelink Shared Channel), the PSSCH (Physical Sidelink Shared Channel), the PSDCH (Physical Sidelink Discovery Channel), and the PSBCH (Physical Sidelink Broadcast Channel) to another user device 20 as D2D communication. ) And the like, and the receiving unit 120 receives a PSCCH, a PSSCH, a PSDCH, a PSBCH, or the like from another user apparatus 20.

The setting unit 230 stores various setting information received from the base station device 10 or the user device 20 by the receiving unit 220 in a storage device, and reads out the setting information from the storage device as needed. The setting unit 230 also stores preset setting information. The content of the setting information is, for example, information related to a reference signal of the D2D communication.

The control unit 240 controls the D2D communication performed with another user device 20 as described in the embodiment. Further, the control unit 240 executes a process related to the reference signal of the D2D communication. A function unit related to signal transmission in control unit 240 may be included in transmission unit 210, and a function unit related to signal reception in control unit 240 may be included in reception unit 220.

(Hardware configuration)
The functional configuration diagrams (FIGS. 7 and 8) used in the above description of the embodiment of the present invention show blocks of functional units. These functional blocks (components) are realized by an arbitrary combination of hardware and / or software. The means for implementing each functional block is not particularly limited. That is, each functional block may be realized by one device in which a plurality of elements are physically and / or logically combined, or two or more devices physically and / or logically separated from each other directly and And / or indirectly (for example, wired and / or wireless), and may be implemented by these multiple devices.

For example, both the base station device 10 and the user device 20 according to an embodiment of the present invention may function as a computer that performs processing according to the embodiment of the present invention. FIG. 9 is a diagram illustrating an example of a hardware configuration of a wireless communication device that is the base station device 10 or the user device 20 according to the embodiment of the present invention. Each of the above-described base station device 10 and user device 20 is physically a computer device including a processor 1001, a storage device 1002, an auxiliary storage device 1003, a communication device 1004, an input device 1005, an output device 1006, a bus 1007, and the like. It may be configured.

In the following description, the term “apparatus” can be read as a circuit, a device, a unit, or the like. The hardware configuration of the base station device 10 and the user device 20 may be configured to include one or more of the devices indicated by 1001 to 1006 illustrated in the drawing, or may be configured without including some devices. May be done.

The functions of the base station device 10 and the user device 20 are performed by reading predetermined software (program) on hardware such as the processor 1001 and the storage device 1002, so that the processor 1001 performs an arithmetic operation. This is realized by controlling reading and / or writing of data in the storage device 1002 and the auxiliary storage device 1003.

The processor 1001 controls the entire computer by operating an operating system, for example. The processor 1001 may be configured by a central processing unit (CPU: Central Processing Unit) including an interface with a peripheral device, a control device, an arithmetic device, a register, and the like.

The processor 1001 reads a program (program code), a software module, or data from the auxiliary storage device 1003 and / or the communication device 1004 to the storage device 1002, and executes various processes according to these. As the program, a program that causes a computer to execute at least a part of the operation described in the above embodiment is used. For example, the transmission unit 110, the reception unit 120, the setting unit 130, and the control unit 140 of the base station device 10 illustrated in FIG. 7 may be realized by a control program stored in the storage device 1002 and operated by the processor 1001. Further, for example, the transmission unit 210, the reception unit 220, the setting unit 230, and the control unit 240 of the user device 20 illustrated in FIG. 8 are realized by a control program stored in the storage device 1002 and operated by the processor 1001. Is also good. Although it has been described that the various processes described above are executed by one processor 1001, the processes may be executed simultaneously or sequentially by two or more processors 1001. Processor 1001 may be implemented with one or more chips. Note that the program may be transmitted from a network via a telecommunication line.

The storage device 1002 is a computer-readable recording medium, and is, for example, at least one of a ROM (Read Only Memory), an EPROM (Erasable Programmable ROM), an EEPROM (Electrically Erasable Programmable ROM), and a RAM (Random Access Memory). It may be configured. The storage device 1002 may be called a register, a cache, a main memory (main storage device), or the like. The storage device 1002 can store a program (program code), a software module, and the like that can be executed to execute the processing according to an embodiment of the present invention.

The auxiliary storage device 1003 is a computer-readable recording medium, for example, an optical disk such as a CD-ROM (Compact Disc ROM), a hard disk drive, a flexible disk, a magneto-optical disk (for example, a compact disk, a digital versatile disk, Blu -Ray (registered trademark) disk), smart card, flash memory (eg, card, stick, key drive), floppy (registered trademark) disk, magnetic strip, or the like. The auxiliary storage device 1003 may be called an auxiliary storage device. The storage medium described above may be, for example, a database including the storage device 1002 and / or the auxiliary storage device 1003, a server, or any other appropriate medium.

The communication device 1004 is hardware (transmitting / receiving device) for performing communication between computers via a wired and / or wireless network, and is also referred to as, for example, a network device, a network controller, a network card, a communication module, and the like. For example, the transmitting unit 110 and the receiving unit 120 of the base station device 10 may be realized by the communication device 1004. Further, the transmission unit 210 and the reception unit 220 of the user device 20 may be realized by the communication device 1004.

The input device 1005 is an input device (for example, a keyboard, a mouse, a microphone, a switch, a button, a sensor, and the like) that receives an external input. The output device 1006 is an output device (for example, a display, a speaker, an LED lamp, and the like) that performs output to the outside. Note that the input device 1005 and the output device 1006 may have an integrated configuration (for example, a touch panel).

The devices such as the processor 1001 and the storage device 1002 are connected by a bus 1007 for communicating information. The bus 1007 may be configured by a single bus, or may be configured by a different bus between the devices.

The base station device 10 and the user device 20 are respectively a microprocessor, a digital signal processor (DSP: Digital Signal Processor), an ASIC (Application Specific Integrated Circuit), a PLD (Programmable Logic Device), an FPGA (Field Programmable Gate Array), and the like. And some or all of the functional blocks may be realized by the hardware. For example, the processor 1001 may be implemented by at least one of these hardware.

(Summary of Embodiment)
As described above, according to the embodiment of the present invention, a receiving unit that receives information related to the arrangement of reference signals used for direct communication between terminals from a base station device or a first user device, A control unit that determines a signal for direct terminal-to-terminal communication based on information related to an arrangement of reference signals used for direct terminal-to-terminal communication, and a transmission that transmits the determined signal for direct terminal-to-terminal communication to a second user apparatus A user apparatus is provided, wherein the information on the arrangement of the reference signal used for the direct communication between terminals includes the transmission density of the reference signal used for the direct communication between terminals.

With the above configuration, even in an unstable communication environment where the relative speed between the user devices changes rapidly, direct communication between terminals can be continued by dynamically switching the arrangement pattern of the reference signals. That is, in the direct communication between terminals, an appropriate reference signal can be used.

The information on the arrangement of the reference signal used for the terminal-to-terminal direct communication includes at least one of the following 1) to 5), and is transmitted via signaling of a PHY (Physical) layer or a MAC (Media access control) layer. It may be received.
1) Mapping pattern in frequency domain and time domain in resource or resource pool 2) Start position and end position of RE (Resource element) where reference signal is placed 3) RE interval where reference signal is placed 4) Reference signal 5) Index of the slot in which the reference signal is allocated. This configuration enables the allocation pattern of the reference signal to be specified in detail, and enables high-speed signaling by the PHY layer or the MAC layer. In addition, a reference signal can be dynamically specified.

When receiving information related to the arrangement of reference signals used for terminal-to-terminal direct communication from the first user apparatus, the information is used for terminal-to-terminal direct communication based on a sequence of reference signals transmitted by the first user apparatus. Information regarding the arrangement of the reference signal may be obtained implicitly. With this configuration, it is possible to acquire information on the arrangement of reference signals with a small overhead.

The information related to the arrangement of the reference signal used for the terminal-to-terminal direct communication is based on the feedback related to the reception of the terminal-to-terminal direct communication signal transmitted from the second user apparatus to the base station apparatus or the first user apparatus. It may be determined based on this. With this configuration, it is possible to arrange the reference signal that follows the communication state of the user device 20 that has received the signal in which the reference signal is arranged. That is, based on the feedback acquired from the user equipment on the receiving side, by switching to the reference signal arrangement pattern determined by the base station apparatus or the user equipment, it is possible to perform direct terminal-to-terminal communication adapted to the communication environment.

The terminal-to-terminal direct communication is a multicast or broadcast, and when there are a plurality of feedbacks related to the reception of the signal of the terminal-to-terminal direct communication, the feedback having the worst reception condition among the plurality of feedbacks, the most feedback among the plurality of feedbacks The information related to the arrangement of the reference signal used for the direct communication between the terminals may be determined based on either the feedback in which the reception status is good or the reception status in which the median value or the average value of the plurality of feedbacks is obtained. With this configuration, it is possible to switch to an appropriate reference signal arrangement pattern when the communication is multicast or broadcast.

Further, according to the embodiment of the present invention, a transmitting unit that transmits information related to the arrangement of reference signals used for direct communication between terminals to the user device, and an arrangement of reference signals used for direct communication between the terminals. A receiving unit that receives feedback related to reception of a signal of direct communication between terminals determined based on information from another user apparatus, and based on feedback related to reception of a signal of direct communication between terminals, the direct communication between the terminals. A control unit that determines information related to the arrangement of the reference signal used for communication, and the information related to the arrangement of the reference signal used for the direct communication between the terminals is a transmission density of the reference signal used for the direct communication between the terminals. Are provided.

(Supplement to the embodiment)
Although the embodiments of the present invention have been described above, the disclosed invention is not limited to such embodiments, and those skilled in the art can understand various modifications, modification examples, alternative examples, substitution examples, and the like. There will be. Although the description has been made using specific numerical examples to facilitate the understanding of the invention, unless otherwise specified, those numerical values are merely examples, and any appropriate values may be used. The division of the items in the above description is not essential to the present invention, and the items described in two or more items may be used in combination as needed, or the items described in one item may be replaced by another item. (Unless inconsistent). The boundaries between functional units or processing units in the functional block diagrams do not always correspond to the boundaries between physical components. The operation of a plurality of functional units may be physically performed by one component, or the operation of one functional unit may be physically performed by a plurality of components. In the processing procedure described in the embodiment, the order of the processing may be changed as long as there is no contradiction. Although the base station device 10 and the user device 20 have been described using a functional block diagram for convenience of description of the process, such a device may be realized by hardware, software, or a combination thereof. The software operated by the processor of the base station apparatus 10 according to the embodiment of the present invention and the software operated by the processor of the user apparatus 20 according to the embodiment of the present invention are a random access memory (RAM), a flash memory, and a read memory, respectively. The data may be stored in a dedicated memory (ROM), an EPROM, an EEPROM, a register, a hard disk (HDD), a removable disk, a CD-ROM, a database, a server, or any other suitable storage medium.

通知 In addition, the notification of information is not limited to the aspect / embodiment described in this specification, and may be performed by another method. For example, the notification of information includes physical layer signaling (for example, DCI (Downlink Control Information), UCI (Uplink Control Information)), upper layer signaling (for example, RRC (Radio Resource Control) signaling, MAC (Medium Access Control) signaling, It may be implemented by broadcast information (MIB (Master Information Block), SIB (System Information Block)), other signals, or a combination thereof, and RRC signaling may be called an RRC message, for example, RRC message. A connection setup (RRC （Connection Setup) message, an RRC connection reconfiguration (RRC Connection Reconfiguration) message, or the like may be used.

Each aspect / embodiment described in this specification includes LTE (Long Term Evolution), LTE-A (LTE-Advanced), SUPER 3G, IMT-Advanced, 4G, 5G, FRA (Future Radio Access), W-CDMA. (Registered trademark), GSM (registered trademark), CDMA2000, UMB (Ultra Mobile Broadband), IEEE 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802.20, UWB (Ultra-WideBand), The present invention may be applied to a system using Bluetooth (registered trademark), another appropriate system, and / or a next-generation system extended based on the system.

処理 The processing procedures, sequences, flowcharts, and the like of each aspect / embodiment described in this specification may be permuted as long as there is no inconsistency. For example, the methods described herein present elements of various steps in a sample order, and are not limited to the specific order presented.

The specific operation described as being performed by the base station device 10 in this specification may be performed by an upper node (upper node) in some cases. In a network including one or a plurality of network nodes (network @ nodes) including the base station device 10, various operations performed for communication with the user device 20 are different from the base station device 10 and / or the base station device 10. It is clear that this can be done by other network nodes (for example, but not limited to MME or S-GW etc.). Although the case where the number of other network nodes other than the base station device 10 is one has been described above, a combination of a plurality of other network nodes (for example, MME and S-GW) may be used.

各 Each aspect / embodiment described in this specification may be used alone, may be used in combination, or may be switched with execution.

The user equipment 20 may be provided by one of ordinary skill in the art to a subscriber station, mobile unit, subscriber unit, wireless unit, remote unit, mobile device, wireless device, wireless communication device, remote device, mobile subscriber station, access terminal, mobile terminal, It may also be called a wireless terminal, remote terminal, handset, user agent, mobile client, client, or some other suitable term.

The base station device 10 may also be referred to by those skilled in the art as an NB (NodeB), an eNB (evolved NodeB), a gNB, a base station (Base の他 Station), or some other suitable terminology.

用語 As used herein, the terms “determining” and “determining” may encompass a wide variety of operations. “Judgment” and “decision” are, for example, judgment (judging), calculation (computing), processing (processing), deriving (investigating), and investigating (looking up) (for example, a table). , A search in a database or another data structure), ascertaining, etc. may be considered as "determined", "determined", etc. Also, “determining” and “determining” refer to receiving (eg, receiving information), transmitting (eg, transmitting information), input (input), output (output), access (Accessing) (e.g., accessing data in the memory) may be regarded as "determined" or "determined". In addition, “judgment” and “decision” mean that resolving, selecting, choosing, choosing, establishing, comparing, etc. are regarded as “judgment” and “determined”. May be included. In other words, “judgment” and “decision” may include deeming any operation as “judgment” and “determined”.

記載 The term "based on" as used herein does not mean "based solely on" unless stated otherwise. In other words, the phrase "based on" means both "based only on" and "based at least on."

As long as “include”, “including”, and variations thereof, are used in the present description or claims, these terms are equivalent to the term “comprising” It is intended to be comprehensive. Further, it is intended that the term "or", as used herein or in the claims, not be the exclusive OR.

Throughout this disclosure, where translations add articles, such as a, an, and the in English, these articles may be used in plurals unless the context clearly indicates otherwise. May be included.

In the embodiment of the present invention, the transmission pattern of SL-PTRS and / or SL-CSI-RS is an example of information related to the arrangement of reference signals used for direct communication between terminals. The user device 20 having the scheduling capability is an example of a first user device. The receiving-side user device 20B is an example of a second user device.

Although the present invention has been described in detail, it will be apparent to those skilled in the art that the present invention is not limited to the embodiments described in this specification. The present invention can be embodied as modified and changed aspects without departing from the spirit and scope of the present invention defined by the description of the claims. Therefore, the description in the present specification is for the purpose of illustrative explanation, and does not have any restrictive meaning to the present invention.

Reference Signs List 10 base station apparatus 110 transmitting section 120 receiving section 130 setting section 140 control section 20 user apparatus 210 transmitting section 220 receiving section 230 setting section 240 control section 1001 processor 1002 storage device 1003 auxiliary storage device 1004 communication device 1005 input device 1006 output device

Claims

A receiving unit that receives information related to the arrangement of reference signals used for direct communication between terminals from the base station device or the first user device,
A control unit that determines a signal for direct communication between terminals based on information related to an arrangement of reference signals used for direct communication between terminals,
A transmitting unit that transmits the signal of the determined direct terminal-to-terminal communication to the second user device,
The user apparatus, wherein the information on the arrangement of the reference signal used for the direct communication between terminals includes the transmission density of the reference signal used for the direct communication between terminals.
The information on the arrangement of the reference signal used for the terminal-to-terminal direct communication includes at least one of the following 1) to 5), and is transmitted via signaling of a PHY (Physical) layer or a MAC (Media access control) layer. The user equipment according to claim 1, which is received.
1) Mapping pattern in frequency domain and time domain in resource or resource pool 2) Start position and end position of RE (Resource element) where reference signal is placed 3) RE interval where reference signal is placed 4) Reference signal 5) RB (Resource block) interval in which reference signal is allocated 5) Index of slot in which reference signal is allocated
When receiving information related to the arrangement of reference signals used for terminal-to-terminal direct communication from the first user apparatus, the information is used for terminal-to-terminal direct communication based on a sequence of reference signals transmitted by the first user apparatus. The user apparatus according to claim 1, wherein the information regarding the arrangement of the reference signal is implicitly obtained.
The information related to the arrangement of the reference signal used for the terminal-to-terminal direct communication is based on the feedback related to the reception of the terminal-to-terminal direct communication signal transmitted from the second user apparatus to the base station apparatus or the first user apparatus. The user apparatus according to claim 1, wherein the user apparatus is determined based on the user apparatus.
The terminal-to-terminal direct communication is a multicast or broadcast, and when there are a plurality of feedbacks related to the reception of the signal of the terminal-to-terminal direct communication, the feedback having the worst reception condition among the plurality of feedbacks, the most feedback among the plurality of feedbacks The information relating to the arrangement of reference signals used for the direct communication between terminals is determined based on one of a reception state in which a reception state is good and a reception state in which a median value or an average value of the plurality of feedbacks is obtained. User equipment.
A transmitting unit that transmits information related to the arrangement of reference signals used for direct communication between terminals to the user device,
A receiving unit that receives feedback related to reception of a signal of direct communication between terminals determined based on information related to the arrangement of the reference signal used for the direct communication between terminals from another user device,
Based on the feedback related to the reception of the signal of the terminal-to-terminal direct communication, having a control unit that determines information related to the arrangement of the reference signal used for the terminal-to-terminal direct communication,
The base station apparatus, wherein the information on the arrangement of the reference signal used for the inter-terminal direct communication includes a transmission density of the reference signal used for the inter-terminal direct communication.